Thermoplastic carbon composite electrodes

Abstract

A new solvent-based method is presented for making low-cost composite graphite electrodes containing a thermoplastic binder. The electrodes, termed thermoplastic electrodes (TPEs), are easy to fabricate and pattern, give excellent electrochemical performance, and have high conductivity (1500 S m−1). The thermoplastic binder enables the electrodes to be hot embossed, molded, templated, and / or cut with a CO2 laser into a variety of intricate patterns. These electrodes show a marked improvement in peak current, peak separation, and resistance to charge transfer over traditional carbon electrodes. The impact of electrode composition, surface treatment (sanding, polishing, plasma treatment), and graphite source were found to impact fabrication, patterning, conductivity, and electrochemical performance. Under optimized conditions, electrodes generated responses similar to more expensive and difficult to fabricate graphene and highly oriented pyrolytic graphite electrodes. These TPE electrodes provide an approach for fabricating high-performance carbon electrodes with applications ranging from sensing to batteries.

Description

RELATED APPLICATIONS[0001]This application is a continuation application, filed under 35 U.S.C. § 111(a), of International Application No. PCT / US2018 / 017094 filed Feb. 6, 2018, which claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Patent Application No. 62 / 455,748 filed Feb. 7, 2017, which applications are incorporated herein by reference.GOVERNMENT SUPPORT[0002]This invention was made with government support under grant 1710222 awarded by National Science Foundation and grant R01 OH010662 awarded by Center for Disease Control. The government has certain rights in the invention.BACKGROUND OF THE INVENTION[0003]Solid state, and quasi solid state, carbon composite electrodes have been known and implemented as far back as 57 years ago. The initial work often utilized a wax material, epoxy, or plastics like poly(methylmethacrylate), Teflon, polyethylene. Some of the advantages of working with a solid state composite electrode are a sandable surface, which can be repeatedly ...

AI Technical Summary

Benefits of technology

The patent text describes a new kind of electrode that is cheap, easy to make and modify, with low electrical resistance and high activity. These electrodes can be used in a variety of applications including sensors, batteries, and disposable one-use electrodes. The electrodes are made by mixing a thermoplastic binder with a carbon allotrope, which results in a smooth electrode surface. The electrodes have a high conductivity, making them better than traditional carbon electrodes. The patent also describes a method for preparing the electrodes by dissolving the binder, combining it with the carbon allotrope, partially drying it, shaping it, and etching the binder to expose the carbon allotrope. Overall, the electrodes described in this patent offer an affordable and customizable solution for various electrochemical applications.

Problems solved by technology

The resulting SPE are typically incompatible with popular organic solvents used in electrochemistry.

In a sensor, low activity of SPE can cause problems with multiple analyte detection (poor resolution), as well as detection limits.

Higher cell resistances make SPEs a poor choice for kinetic measurements, limiting their use in fundamental electrochemical research.

Lastly, SPE are typically crudely coupled with complex electrochemical systems such as microfluidics because they are not directly integrated into the microfluidic substrate.

Despite their widespread use, traditional carbon composite electrodes have substandard electrochemistry relative to metallic and glassy carbon electrodes.

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